Answer:
B. 0.72
Step-by-step explanation:
In order to find the answer we need to use the following formula:
\(a^2=b^2+c^2-2bc*cos(\theta)\) where:
a, b, c are the length of the sides and \(\theta\) the angle, so:
\(7^2=10^2+8^2-(2*10*8)*cos(\theta)\)
\(49=164-(160)*cos(\theta)\)
\(cos(\theta)=0.71875\)
In conclusion, \(cos(\theta)=0.72\), so the answer is B.
